The Bombe Machine

Introduction

The Bombe was a bank of rotating drums, each wired like an Enigma rotor. For every possible rotor position, it asked: could these letter pairings all be true?

If the circuit forced a letter to equal itself, that position was impossible. The drums kept turning until only the true daily key remained.

Key ideaThe Bombe wires the menu into a circuit. A contradiction lights up; a valid setting leaves the circuit dark.